Pressure relief valve



FIG. 1 is a front elevation view of a pressure relief valve showing our new design, the rear view being a mirror image of FIG. 1.

FIG. 2 is a first side elevation view of FIG. 1, the opposite side view being a mirror image thereof.

FIG. 3 is a top plan view of FIG. 1.

FIG. 4 is a bottom plan view of FIG. 1.

FIG. 5 is a top perspective view of FIG. 1; and,

FIG. 6 is a bottom perspective view of FIG. 1.

The broken lines shown in the figures are for the purpose of illustrating portions of the pressure relief valve and form no part of the claimed design. 

CLAIM The ornamental design for a pressure relief valve, as shown and described. 